LTC4300-1IMS8#PBF

Signal Buffers, Repeaters, Splitters Overview

The LTC4300-1IMS8#PBF is a hot swappable 2-wire bus buffer designed for I2C and SMBus applications. It allows bidirectional buffering of SDA and SCL lines while isolating backplane and card capacitances during live insertion. The device operates with a supply voltage range of 2.7V to 5.5V and supports data rates up to 400kHz. Key electrical parameters include a propagation delay (tPHL) of 75ns, an input capacitance of 10pF, and a shutdown supply current of less than 1µA when the ENABLE pin is grounded. It features a 1V precharge circuitry to minimize bus disturbances upon connection.

Signal Buffers, Repeaters, Splitters Feature Summary

• Provides bidirectional buffering for SDA and SCL lines to prevent data corruption during hot swapping
• Incorporates rise time accelerator circuitry to allow weaker DC pull-up currents while meeting timing requirements
• Features a CMOS threshold digital ENABLE input pin that forces low current mode when driven to ground
• Includes an open-drain READY output pin indicating successful connection between backplane and card sides

Signal Buffers, Repeaters, Splitters Applications

• Bidirectional buffer for SDA and SCL lines in server systems
• Hot board insertion into live backplanes without signal corruption
• Capacitance buffering and bus extension for desktop computers

Signal Buffers, Repeaters, Splitters Procurement Notes

Verify the specific suffix IMS8 indicates the industrial temperature range (-40°C to +85°C) and MSOP package. Confirm PBF denotes lead-free finish. Ensure the ENABLE pin configuration matches the -1 variant requirements rather than the -2 variant which uses VCC2. Check datasheet for proper pull-up resistor selection based on system capacitance.

Signal Buffers, Repeaters, Splitters Selection Notes

Select this part for applications requiring isolation between backplane and card capacitances during hot swap events. The ENABLE pin allows for external control of the buffer state, enabling low power modes. Ensure the system pull-up resistors are selected to provide a positive slew rate of at least 1.25V/µs to activate the rise time accelerators effectively.

Signal Buffers, Repeaters, Splitters Part Context

This component belongs to the LTC4300 series of hot swappable 2-wire bus buffers. The -1 variant specifically utilizes an ENABLE pin for control and a READY output flag. It is distinct from the -2 variant which replaces these with a dedicated VCC2 supply and ACC input for level shifting between 3.3V and 5V systems.

Signal Buffers, Repeaters, Splitters Replacement Considerations

The LTC4300-2IMS8#PBF serves as a functional alternative if level shifting between disparate supply voltages is required, though it lacks the ENABLE and READY pins.